Antenna.



R. H. RENDAHL.l

ANTENNA.

APPLIOATIONIILBD JUNE 7, 1910.

Patented Oct. 10, 1911.

11.2. a I h/@- Wima55e.

l encarar.

RAG-NAR E. RENDAHL, OIE LLJ'EHOLMEN, NEAR STOCKHOLM, SWEDEN.

ANTENNA.

Speciication of Letters Patent.

Patented oet. io, ieri.

Application filed .Tune 7, 1910. Serial No. 565,594.

To all whom it may cof/wem:

Be it known that l, RAGNAR HAKAN REN- DAHL, a subject or" the King of Sweden, and residing at Liljeholmen, near Stockholm, Sweden, have invented certain new and useful improvements in Antennae, of which the following is a specification. f

My invention relates to antenn for wireless telegraphy and the like.

The maximum energy which can be brought into an antenna of a given shape without material losses'is principally governed by the tension in the antenna. The greater the diameter of the wires and with it the radius of curvature, the more energy can the antenna take up without losses occurring owing to scintillating discharges. For this reason it has been endeavored to protect particularly the ends of serial Wires from4 scintillating losses by means of balls or the like placed thereon. Also, various kinds of material have been proposed for antennae in order to obtain a large diameter in spite of small Weight. Nevertheless all measures proposed heretofore have only been accompanied with but little success.

According to my invention I attain the end in view substantially by making the antenna principally of thin metal tubes of large diameter which are placed flexibly one against the otherlinrows. Such an antenna can be formed, for example, by pushing metal tubes over the aerial wire as has been done heretofore, the individual tubes being closed at their ends with the exception of small concentric holes by means of which the tubes are drawn over the wire.

One illustrative 'embodiment of my inve tion is represented by way of example in the accompanying drawing, wherein Y Figure 1 is an elevation, partly in vertical section, showing one form of my improved antenna, and Fig. 2 is, a cross-section through the same. Fig. 3 is an elevation, partly in section, showing a modified form of coupling.

Referring to the drawing, a designates the wire carrying the tubes b. According to the size of the antennae the tubes may be of various lengths, e.. g. half ameter to two meters, and are threaded close together in a row on the wire. one hand sufficient. movability of the andiameter vthreaded thereon in a row,

elastic, good electrically-conducting mem- In this manner. on the tenna is obtained, and, on the other hand, in spite of less weight the desired large diameter and large radius of curvature are obtained. In order to make a good conducting connection between the tubes and .the wires carrying them, which is important particularly when receiving, elastic connecting members c or the like may be arranged at or in the tubes. As wire for carrying the tubes, besides the materials customary heretofore steel wire may be employed, whose surface is preferably provided with a better conducting coating for producing a good conductor with g'ood contact. lt is also possible to secure 'together the ends of the tubes by hooks or the like as shown at al, in Fig. 3 and thus to combine the individual parts to form an entirety without an internal wire. Then, for obtaining good conductivity, the individual tubes must be well connected t0- gethcr electrically in suitable manner, and on the other hand, for avoiding scintillating losses, the joints betwee'n the tubes must be surrounded with ball-like structures for example, as shown at 6 in Fig. 3.

The described antenna can be employed wire, and a plurality of thin metal tubesof large diameter threaded thereon in a row, substantially as shown.

3. .An antenna for the purposes rot -radiotelegraphy, comprising `in combination a wire, a plurality of thin metal tubes of lrge an an ber arranged between each tube and the wire, substantially as shown.

Witnesses HOWARD NYeTRoM, HEDWIG MELINDER.

RAGNA-R H. RENDAHLi roo 

